ABSTRACT
Antecedentes: Los dermatofitos son un grupo de hongos queratinolíticos que producen infecciones denominadas dermatofitosis o tiñas. En Chile, los dermatofitos aislados con mayor frecuencia son Trichophyton rubrumy Trichophyton mentagrophytes en la población adulta, y Microsporum canis en niños prepúberes. Para el tratamiento de estas micosis se emplean antifúngicos tópicos y orales como la griseofulvina, antifúngicos azólicos como el clotrimazol, el itraconazol o el fluconazol, alilaminas como la terbinafina, y nuevas moléculas antifúngicas. Objetivos: Evaluar la sensibilidad in vitro de los dermatofitos frente a cinco antifúngicos y establecer posibles cambios respecto a estudios anteriores. Métodos: Se estudiaron 62 dermatofitos obtenidos de muestras clínicas (marzo-junio de 2010). Se utilizó el método de microdilución en caldo (M38-A2). Resultados: El rango de CMI para el fluconazol fue de 0,25-1 μg/ml; 0,03-0,06 μg/ml para el clotrimazol, la terbinafina y el itraconazol, y 0,015-0,03 μg/ml para la griseofulvina frente a T. rubrum y T. mentagrophytes. Excepto para le fluconazol, no se encontraron diferencias estadísticas significativas en los rangos de sensibilidad antifúngica. Conclusiones: Los valores de CMI para el fluconazol fueron los más altos (0,25-1 μg/ml) de todas las sustancias ensayadas, habiendo diferencias estadísticamente significativas entre este y el resto de antifúngicos. No hubo cepas resistentes a los antifúngicos analizados, y tampoco se encontraron cambios en el perfil de sensibilidad antifúngica in vitro en relación con estudios anteriores realizados en Chile (AU)
Background: Dermatophytes are a group of keratinophilic fungi able to produce dermatophytosis or tinea infections. In Chile, Trichophyton rubrum and Trichophyton mentagrophytes are the ones most commonly isolated in adults, while Microsporum canis is found among children. Treatment of these infections is usually with topical or oral antifungals, such as griseofulvin or azole derivatives (clotrimazole, itraconazole, fluconazole), allylamines (terbinafine) or new drugs that are available. Aims: Evaluation of the in vitro susceptibility of dermatophytes to five antifungal agents and the comparison of the susceptibility pattern with that of previous years. Methods: Sixty-two clinical isolates of dermatophyte fungi were studied (March-June 2010). The CLSI M38-A2 micromethod was used. Results: Fluconazole MIC values for T. rubrum and T. mentagrophytes varied between 0.25 and 1 μg/ml; MIC range to clotrimazole, terbinafine and itraconazole was 0.03-0.06 μg/ml, and MIC values for griseofulvin were 0.015-0.03 μg/ml. No statistically significant differences were found between susceptibility patterns, except for fluconazole. Conclusions: Fluconazole was less active in comparison with other drugs tested (0.25-1 μg/ml). None of the isolates were resistant to any of the drugs, and no changes in the susceptibility pattern were observed when comparing the results with data previously reported concerning dermatophytes in Chile (AU)
Subject(s)
Humans , Trichophyton/pathogenicity , Arthrodermataceae/pathogenicity , Antifungal Agents/pharmacokinetics , In Vitro Techniques/methods , Microbial Sensitivity Tests , Fluconazole/pharmacokinetics , Trimethoprim, Sulfamethoxazole Drug Combination/pharmacokinetics , Griseofulvin/pharmacokinetics , Itraconazole/pharmacokineticsABSTRACT
BACKGROUND: Dermatophytes are a group of keratinophilic fungi able to produce dermatophytosis or tinea infections. In Chile, Trichophyton rubrum and Trichophyton mentagrophytes are the ones most commonly isolated in adults, while Microsporum canis is found among children. Treatment of these infections is usually with topical or oral antifungals, such as griseofulvin or azole derivatives (clotrimazole, itraconazole, fluconazole), allylamines (terbinafine) or new drugs that are available. AIMS: Evaluation of the in vitro susceptibility of dermatophytes to five antifungal agents and the comparison of the susceptibility pattern with that of previous years. METHODS: Sixty-two clinical isolates of dermatophyte fungi were studied (March-June 2010). The CLSI M38-A2 micromethod was used. RESULTS: Fluconazole MIC values for T. rubrum and T. mentagrophytes varied between 0.25 and 1 µg/ml; MIC range to clotrimazole, terbinafine and itraconazole was 0.03-0.06 µg/ml, and MIC values for griseofulvin were 0.015-0.03 µg/ml. No statistically significant differences were found between susceptibility patterns, except for fluconazole. CONCLUSIONS: Fluconazole was less active in comparison with other drugs tested (0.25-1 µg/ml). None of the isolates were resistant to any of the drugs, and no changes in the susceptibility pattern were observed when comparing the results with data previously reported concerning dermatophytes in Chile.
